1. Field Of Invention
This invention relates to hand tools and is particularly directed to a hand tool for extracting the riser of pop-up type water sprinklers and the like.
2. Prior Art
Wherever there are lawns or gardens, there is a necessity for frequent watering. To accomplish such watering by having someone stand and sprinkle the area with a hose is extremely time consuming and, with today's labor costs, is prohibitively expensive. To overcome these problems, it has been common to provide a plurality of sprinkler heads placed at desired locations about the area and connected by buried pipes to a common source of water. Originally, these sprinkler heads were mounted several inches above the surface of the ground on vertical pipes which extended upward from the buried supply pipes. However, these above-ground sprinkler heads were often unsightly and presented a hazard to persons, especially children, walking or running in the vicinity.
More recently, it has become the practice to provide sprinkler heads which are mounted on risers that lie below the surface of the ground, when the sprinkler is not in use, and which, when the water is turned "On", are forced upward to their operative positions by hydraulic pressure. These pop-up sprinklers overcome most of the disadvantages of the earlier above-ground sprinklers. However, the pop-up sprinklers present unique problems when they require servicing. The risers of the pop-up sprinklers are mounted in housings which are buried below the surface of the ground and are normally urged, by a strong spring, to a retracted position within the housing. When the sprinkler system is turned "On", the water pressure forces the risers upward, against the action of the spring, to their operative position and some of the water passes through the sprinkler head to be distributed to the lawn or garden area. Since servicing of the sprinkler heads must be performed when the sprinklers are not in operation, the pop-up type sprinkler heads will be in their retracted positions and some means must be provided to force the risers upward, against the action of their springs, in order to gain access to the heads. Furthermore, since a considerable amount of water is often present in the vicinity of the riser and sprinkler head during servicing, tools used is such servicing are often damaged or destroyed by rust. Also, prior to the nozzle being applied to the head, during installation, dirt and other obstruction can impair the ability of the spring-retracted riser from receiving the required nozzle until the riser has been cleaned, which usually involves lifting the riser while water flows through the head. This is often a difficult and time-consuming task.
In the past, no tool has been provided specifically for this purpose and it has been necessary for service personnel to improvise their own methods and apparatus for lifting the risers and servicing the sprinkler heads. Unfortunately, these improvised methods are often unsuccessful, difficult to perform and may result in damage to the sprinkler head or riser. A search in the U.S. patent Office has revealed the following references:
______________________________________ U.S. Pat. No. INVENTOR ISSUED ______________________________________ 2,497,633 J. Shapiro et al Feb. 14, 1950 2,694,603 F. R. Griffin Nov. 16, 1954 2,847,752 J. T. Simmons Aug. 19, 1958 2,947,074 C. M. Newman Aug. 2, 1960 3,138,855 C. D. Marshall June 30, 1964 3,210,832 G. H. Kalen Oct. 12, 1965 3,588,983 R. C. Hoy June 29, 1971 3,654,686 F. R. McFarland et al Apr. 11, 1972 4.050,148 J. K. Hastings Sep. 27, 1977 4,052,788 J. K. Hastings et al Oct. 11, 1977 4,096,617 A. J. Ritter, Jr. June 27, 1978 4,184,245 W. R. Mattingly, Jr. Jan. 22, 1980 4,498,233 C. C. Simms Feb. 12, 1985 4,577,899 J. K. Hemmingway Mar. 25, 1986 4,583,275 E. M. Diaz Apr. 22, 1986 4,746,158 K. L. Fields May 24, 1988 ______________________________________
Each of these references relates to a tool for extracting or removing some object. However, none of the reference patents is concerned with the unique problems involved in lifting sprinkler risers and servicing sprinkler heads. Thus, none of the prior art tools have been entirely satisfactory.